The Animal Farm school of television was founded in 1984, the year in which Terry Wogan opined that the medium shrinks the imagination and decades after a long-forgotten literary guru had damned it for making the manufacture of banality a major industry. The School is a mind-bending, brainwashing, indoctrinating institution devoted to training dim-witted but ambitious adolescents in the art of television.

Dimwitted the students must be, for no lively mind capable of bringing what he is taught to the bar of his own judgment would tolerate the dumbing discipline for longer than a term.

And an art television must claim to be, for art is superior and inviolable, and from the conviction that he is an artist will come the student's arrogance - necessary to ride roughshod over everyone who might plead for intellectual rigour in his work. Here, as I have painfully discovered, he learns by rote the cliché and the platitude, the commonplace and the stereotype, and in adoration bends the knee to mediocrity.

Edward Windsor, Earl of Wessex, was a student at this school, so, too, Alan Yentob, panjandrum of the BBC, and with them every director, cameraman, scriptwriter and dogsbody who has made a programme about culture or the visual arts since, a quarter of a century ago, old Tom Keating was left alone before his easel to show us how to paint a fake.

What are the clichés? The camera swinging away to give us scudding clouds, shimmering water and the topmost twigs of trees. The railway trains rapidissimo through the hills of Tuscany or chugging on an old steam line through the vales of deepest Devon - these too are clichés; so, too, the idiosyncratic car, the bicycle in Holland and the camel in the desert.

How many times have we seen the presenter climbing and descending stairs, turning an unlikely corner or sitting like a mermaid on a rock so that the camera can pretend to discover him by chance. The presenter of every programme on the arts, architecture or plain history will be made to walk from right to left and left to right innumerable times, into and out of shot; he will be compelled to look at things that are not there - let me repeat - that are not there, with simulated joy and awe, so as to lend continuity to a sequence conceived entirely by the director.

Ah, yes, continuity "We have to know how you got there," said a director once, "we can't just have you appearing on the screen" - so endless hours and bottomless pits of cash are wasted on walking shots, driving shots, on shots of planes, trains and bicycles. In Pakistan, where I once contributed to a brief programme on the spread of Buddhism, the leitmotiv was the painted bus.

"Not another bloody bus," groaned I, seeing the cameraman-director reclining in the gutter for an ever more extreme approach shot of the preposterously decorated behemoth, to which his response was: "This is the art of television - a thing you wouldn't understand."

No, I wouldn't (and I dislike the syntax too). I am convinced that, given an hour-long film on Michelangelo's Sistine Chapel paintings, the average director would waste half of it on continuity. As a consumer, my view of factual and interpretive television is that it should inform, enlighten and excite.

As a consumer I shout "Get on with it" in mounting irritation as on the screen appear the hackneyed irrelevances that are the director's devices for not supplying information.

The viewer is contemptuously patronised by these directors. The viewer, they say, cannot absorb more than 15 seconds of information, cannot look at images and listen to facts at the same time.

My arguments - that the presenter should be virtually invisible, that he should never stand in front of whatever it is he seeks to elucidate, waving his arms and shouting, and that no one should watch a programme because the presenter is, like Sister Wendy, entertaining because incongruous and absurd - run counter to the orthodoxy of television, which, by and large, is that the presenter is the director's puppet.

He must kowtow to the director's will, stand shrivelling in the baking sun, speak to the camera in unholy hubbubs of traffic and the human race, tolerate a cameraman who angles his fish-eye lens as though it is essential to count every nostril hair, and be unfailingly benign when the sound-man's battery goes flat.

The rule is that whatever difficulties can, in the interests of spontaneity and happy accident, be accumulated, accumulated they must be to throw him from his stride - anything to prevent him from saying what he wants to say, or saying what he should.

Wessex and Yentob, presenterdirectors wholly in charge of what is said and done as well as every penny spent, are in the privileged position of being able to create a new televisual language, but they remain loyal to their old school and are as utterly dependent on cliché as every other hack.

Yentob on Saatchi - what a subject heaven sent, and yet we were given no insight, no perception, no justification of contemporary art, no aesthetic or intellectual argument, only the mixture as before, the habitual convention, the established order, the stale ritual, a programme without bite, bits of which could well have been reprinted in the pages of Hello! magazine.

From the very top of the BBC, with no expense spared, the best that we can expect is anodyne and familiar formula, utterly unchallenging.

When next you see a lesser presenter on the little screen, clambering about the pyramids, rowing up the Amazon or attempting to say something sensible about a work of art, take pity. The credits may claim that he researched and wrote the script, but the fact is that what the viewer sees and hears bears scant resemblance to what, in the beginning, he hoped you'd see and hear - it has been cut and clipped and bowdlerised.

As pawn and puppet, stooge indeed, he is as much the victim of the patronising director as you, the viewers, are. It is, perhaps, some small consolation that he in turn may be the victim of those who command the five main channels, for it is largely in the dimwittedness of these that the dumbing down of television is well and truly rooted.